The law of cosines is used to find the measures of a triangle when only the three sides are known, because the law of sines requires at least one angle measure.

True or False?

Question

The law of cosines is used to find the measures of a triangle when only the three sides are known, because the law of sines requires at least one angle measure.

True or False?

johnweldon1993 · Answer

This is true...because the law of sines says

$$\frac{ \sin A }{ a } = \frac{ \sin B }{ b } = \frac{ \sin C }{ c }$$

where A, B, and C are angle measurements...a,b and c are the side lengths....

If you do not know at least 1 angle...you cannot use this

anonymous · Answer

Thank you, thats what my book says but its stated in a twisty way

johnweldon1993 · Answer

no problem!